// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "media/base/channel_layout.h"

#include <stddef.h>

#include "base/logging.h"
#include "base/macros.h"

namespace media {

static const int kLayoutToChannels[] = {
    0, // CHANNEL_LAYOUT_NONE
    0, // CHANNEL_LAYOUT_UNSUPPORTED
    1, // CHANNEL_LAYOUT_MONO
    2, // CHANNEL_LAYOUT_STEREO
    3, // CHANNEL_LAYOUT_2_1
    3, // CHANNEL_LAYOUT_SURROUND
    4, // CHANNEL_LAYOUT_4_0
    4, // CHANNEL_LAYOUT_2_2
    4, // CHANNEL_LAYOUT_QUAD
    5, // CHANNEL_LAYOUT_5_0
    6, // CHANNEL_LAYOUT_5_1
    5, // CHANNEL_LAYOUT_5_0_BACK
    6, // CHANNEL_LAYOUT_5_1_BACK
    7, // CHANNEL_LAYOUT_7_0
    8, // CHANNEL_LAYOUT_7_1
    8, // CHANNEL_LAYOUT_7_1_WIDE
    2, // CHANNEL_LAYOUT_STEREO_DOWNMIX
    3, // CHANNEL_LAYOUT_2POINT1
    4, // CHANNEL_LAYOUT_3_1
    5, // CHANNEL_LAYOUT_4_1
    6, // CHANNEL_LAYOUT_6_0
    6, // CHANNEL_LAYOUT_6_0_FRONT
    6, // CHANNEL_LAYOUT_HEXAGONAL
    7, // CHANNEL_LAYOUT_6_1
    7, // CHANNEL_LAYOUT_6_1_BACK
    7, // CHANNEL_LAYOUT_6_1_FRONT
    7, // CHANNEL_LAYOUT_7_0_FRONT
    8, // CHANNEL_LAYOUT_7_1_WIDE_BACK
    8, // CHANNEL_LAYOUT_OCTAGONAL
    0, // CHANNEL_LAYOUT_DISCRETE
    3, // CHANNEL_LAYOUT_STEREO_AND_KEYBOARD_MIC
    5, // CHANNEL_LAYOUT_4_1_QUAD_SIDE
};

// The channel orderings for each layout as specified by FFmpeg. Each value
// represents the index of each channel in each layout.  Values of -1 mean the
// channel at that index is not used for that layout. For example, the left side
// surround sound channel in FFmpeg's 5.1 layout is in the 5th position (because
// the order is L, R, C, LFE, LS, RS), so
// kChannelOrderings[CHANNEL_LAYOUT_5_1][SIDE_LEFT] = 4;
static const int kChannelOrderings[CHANNEL_LAYOUT_MAX + 1][CHANNELS_MAX + 1] = {
    // FL | FR | FC | LFE | BL | BR | FLofC | FRofC | BC | SL | SR

    // CHANNEL_LAYOUT_NONE
    { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 },

    // CHANNEL_LAYOUT_UNSUPPORTED
    { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 },

    // CHANNEL_LAYOUT_MONO
    { -1, -1, 0, -1, -1, -1, -1, -1, -1, -1, -1 },

    // CHANNEL_LAYOUT_STEREO
    { 0, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1 },

    // CHANNEL_LAYOUT_2_1
    { 0, 1, -1, -1, -1, -1, -1, -1, 2, -1, -1 },

    // CHANNEL_LAYOUT_SURROUND
    { 0, 1, 2, -1, -1, -1, -1, -1, -1, -1, -1 },

    // CHANNEL_LAYOUT_4_0
    { 0, 1, 2, -1, -1, -1, -1, -1, 3, -1, -1 },

    // CHANNEL_LAYOUT_2_2
    { 0, 1, -1, -1, -1, -1, -1, -1, -1, 2, 3 },

    // CHANNEL_LAYOUT_QUAD
    { 0, 1, -1, -1, 2, 3, -1, -1, -1, -1, -1 },

    // CHANNEL_LAYOUT_5_0
    { 0, 1, 2, -1, -1, -1, -1, -1, -1, 3, 4 },

    // CHANNEL_LAYOUT_5_1
    { 0, 1, 2, 3, -1, -1, -1, -1, -1, 4, 5 },

    // FL | FR | FC | LFE | BL | BR | FLofC | FRofC | BC | SL | SR

    // CHANNEL_LAYOUT_5_0_BACK
    { 0, 1, 2, -1, 3, 4, -1, -1, -1, -1, -1 },

    // CHANNEL_LAYOUT_5_1_BACK
    { 0, 1, 2, 3, 4, 5, -1, -1, -1, -1, -1 },

    // CHANNEL_LAYOUT_7_0
    { 0, 1, 2, -1, 5, 6, -1, -1, -1, 3, 4 },

    // CHANNEL_LAYOUT_7_1
    { 0, 1, 2, 3, 6, 7, -1, -1, -1, 4, 5 },

    // CHANNEL_LAYOUT_7_1_WIDE
    { 0, 1, 2, 3, -1, -1, 6, 7, -1, 4, 5 },

    // CHANNEL_LAYOUT_STEREO_DOWNMIX
    { 0, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1 },

    // CHANNEL_LAYOUT_2POINT1
    { 0, 1, -1, 2, -1, -1, -1, -1, -1, -1, -1 },

    // CHANNEL_LAYOUT_3_1
    { 0, 1, 2, 3, -1, -1, -1, -1, -1, -1, -1 },

    // CHANNEL_LAYOUT_4_1
    { 0, 1, 2, 4, -1, -1, -1, -1, 3, -1, -1 },

    // CHANNEL_LAYOUT_6_0
    { 0, 1, 2, -1, -1, -1, -1, -1, 5, 3, 4 },

    // CHANNEL_LAYOUT_6_0_FRONT
    { 0, 1, -1, -1, -1, -1, 4, 5, -1, 2, 3 },

    // FL | FR | FC | LFE | BL | BR | FLofC | FRofC | BC | SL | SR

    // CHANNEL_LAYOUT_HEXAGONAL
    { 0, 1, 2, -1, 3, 4, -1, -1, 5, -1, -1 },

    // CHANNEL_LAYOUT_6_1
    { 0, 1, 2, 3, -1, -1, -1, -1, 6, 4, 5 },

    // CHANNEL_LAYOUT_6_1_BACK
    { 0, 1, 2, 3, 4, 5, -1, -1, 6, -1, -1 },

    // CHANNEL_LAYOUT_6_1_FRONT
    { 0, 1, -1, 6, -1, -1, 4, 5, -1, 2, 3 },

    // CHANNEL_LAYOUT_7_0_FRONT
    { 0, 1, 2, -1, -1, -1, 5, 6, -1, 3, 4 },

    // CHANNEL_LAYOUT_7_1_WIDE_BACK
    { 0, 1, 2, 3, 4, 5, 6, 7, -1, -1, -1 },

    // CHANNEL_LAYOUT_OCTAGONAL
    { 0, 1, 2, -1, 5, 6, -1, -1, 7, 3, 4 },

    // CHANNEL_LAYOUT_DISCRETE
    { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 },

    // CHANNEL_LAYOUT_STEREO_AND_KEYBOARD_MIC
    { 0, 1, 2, -1, -1, -1, -1, -1, -1, -1, -1 },

    // CHANNEL_LAYOUT_4_1_QUAD_SIDE
    { 0, 1, -1, 4, -1, -1, -1, -1, -1, 2, 3 },

    // FL | FR | FC | LFE | BL | BR | FLofC | FRofC | BC | SL | SR
};

int ChannelLayoutToChannelCount(ChannelLayout layout)
{
    DCHECK_LT(static_cast<size_t>(layout), arraysize(kLayoutToChannels));
    return kLayoutToChannels[layout];
}

// Converts a channel count into a channel layout.
ChannelLayout GuessChannelLayout(int channels)
{
    switch (channels) {
    case 1:
        return CHANNEL_LAYOUT_MONO;
    case 2:
        return CHANNEL_LAYOUT_STEREO;
    case 3:
        return CHANNEL_LAYOUT_SURROUND;
    case 4:
        return CHANNEL_LAYOUT_QUAD;
    case 5:
        return CHANNEL_LAYOUT_5_0;
    case 6:
        return CHANNEL_LAYOUT_5_1;
    case 7:
        return CHANNEL_LAYOUT_6_1;
    case 8:
        return CHANNEL_LAYOUT_7_1;
    default:
        DVLOG(1) << "Unsupported channel count: " << channels;
    }
    return CHANNEL_LAYOUT_UNSUPPORTED;
}

int ChannelOrder(ChannelLayout layout, Channels channel)
{
    DCHECK_LT(static_cast<size_t>(layout), arraysize(kChannelOrderings));
    DCHECK_LT(static_cast<size_t>(channel), arraysize(kChannelOrderings[0]));
    return kChannelOrderings[layout][channel];
}

const char* ChannelLayoutToString(ChannelLayout layout)
{
    switch (layout) {
    case CHANNEL_LAYOUT_NONE:
        return "NONE";
    case CHANNEL_LAYOUT_UNSUPPORTED:
        return "UNSUPPORTED";
    case CHANNEL_LAYOUT_MONO:
        return "MONO";
    case CHANNEL_LAYOUT_STEREO:
        return "STEREO";
    case CHANNEL_LAYOUT_2_1:
        return "2.1";
    case CHANNEL_LAYOUT_SURROUND:
        return "SURROUND";
    case CHANNEL_LAYOUT_4_0:
        return "4.0";
    case CHANNEL_LAYOUT_2_2:
        return "QUAD_SIDE";
    case CHANNEL_LAYOUT_QUAD:
        return "QUAD";
    case CHANNEL_LAYOUT_5_0:
        return "5.0";
    case CHANNEL_LAYOUT_5_1:
        return "5.1";
    case CHANNEL_LAYOUT_5_0_BACK:
        return "5.0_BACK";
    case CHANNEL_LAYOUT_5_1_BACK:
        return "5.1_BACK";
    case CHANNEL_LAYOUT_7_0:
        return "7.0";
    case CHANNEL_LAYOUT_7_1:
        return "7.1";
    case CHANNEL_LAYOUT_7_1_WIDE:
        return "7.1_WIDE";
    case CHANNEL_LAYOUT_STEREO_DOWNMIX:
        return "STEREO_DOWNMIX";
    case CHANNEL_LAYOUT_2POINT1:
        return "2POINT1";
    case CHANNEL_LAYOUT_3_1:
        return "3.1";
    case CHANNEL_LAYOUT_4_1:
        return "4.1";
    case CHANNEL_LAYOUT_6_0:
        return "6.0";
    case CHANNEL_LAYOUT_6_0_FRONT:
        return "6.0_FRONT";
    case CHANNEL_LAYOUT_HEXAGONAL:
        return "HEXAGONAL";
    case CHANNEL_LAYOUT_6_1:
        return "6.1";
    case CHANNEL_LAYOUT_6_1_BACK:
        return "6.1_BACK";
    case CHANNEL_LAYOUT_6_1_FRONT:
        return "6.1_FRONT";
    case CHANNEL_LAYOUT_7_0_FRONT:
        return "7.0_FRONT";
    case CHANNEL_LAYOUT_7_1_WIDE_BACK:
        return "7.1_WIDE_BACK";
    case CHANNEL_LAYOUT_OCTAGONAL:
        return "OCTAGONAL";
    case CHANNEL_LAYOUT_DISCRETE:
        return "DISCRETE";
    case CHANNEL_LAYOUT_STEREO_AND_KEYBOARD_MIC:
        return "STEREO_AND_KEYBOARD_MIC";
    case CHANNEL_LAYOUT_4_1_QUAD_SIDE:
        return "4.1_QUAD_SIDE";
    }
    NOTREACHED() << "Invalid channel layout provided: " << layout;
    return "";
}

} // namespace media
